two? [laughter] there be. there be. they're called engineers in science types, in physics types. in fact, they're us types, aren't they? what's the wavelength, gang? let's go. watch this, one, one, two, two, three, three, four, four, five, five, now it's 3/14. okay. so wavelength equals 3/14 of a what? - kilometer. - kilometer. okay? that's like 3,000 meters divided by 14. why did you pick a four, man? i mean--how many times does 14 go into 3,000? does anyone have a calculator? 214.28571. 214 meters long. is that surprising to you? that's like two football fields and then some. so the wavelength of your favorite radio station is more than two football fields long. radio waves are long or short compared to light waves, gang? we'll do the same thing for light waves later on and find out it's a smidge, smidge, smidge, smidge, smidge. zero's go the other way. yey. anyway, that's how you find the wavelength of something. i can show you the slinky here. can someone grab the end of this for an "a" in the course. [laughter] right over here. now, i'm gonna take this wave and i'm gonna sh